Field of the Invention
This invention generally relates to imaging systems, and more particularly, to a system and method for generating a graphical user interface from image data, such as video images.
Background Description
Conventional video surveillance systems allow users to view portions of monitored areas by either physically aiming a video camera at a desired portion or by generating a perspective corrected view of the desired portion from a wide angle (e.g., fisheye) image of the monitored area. One shortcoming of such conventional systems is that they do not conveniently enable a user to discern the part of the monitored area represented by the displayed portion. For example, a video surveillance system may display a close-up image of a person or an object (the displayed portion) in a room or a parking lot (the monitored area). Without an image of the entire room or lot and an indication of the area represented by the close-up image, it may be difficult or impossible to quickly determine the position of the person or object in the monitored room or lot. This is especially true for a crowded room or lot, where it may be difficult to distinguish one isolated portion from another.
Another shortcoming is that video surveillance systems typically do not allow an operator to see anything but the portions of monitored areas being displayed. The undisplayed portions may comprise a substantial portion of a monitored area, in which significant activity of interest may occur. For example, if a displayed image represents only 10% of a monitored parking lot, the other 90% may be unmonitored at any given time.
Yet another shortcoming is that high zoom factor images mathematically derived from wide-angle lens image data tend to exhibit low resolution. The greater the zoom factor, the lower the resolution. This impairs an operator's ability to distinguish fine details (e.g., facial features or automobile license plate numbers) in a monitored area.
While the invention overcomes one or more of the problems in conventional video surveillance systems as set forth above, it should be apparent that the invention may have applicability to a wide array of imaging devices and methods, particularly those employing images of moving objects, regardless of the particular format of the image data.